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101.
In a previous publication, (Singer, M.A., Jain, M.K., Sable, H.Z., Pownall, H.H., Mantulin, W.W., Lister, M.D. and Hancock, A.J. (1983) Biochim. Biophys. Acta, 731, 373–377), we reported the properties of aqueous dispersions of the six diastereo-isomers of cyclopentanoid analogues of dipalmitoylphosphatidylcholine. Two of these isomers displayed unusually high enthalpies of transition, about double that of dipalmitoylphosphatidylcholine. One of the high enthalpy isomers whose configuration is all-trans has now been modified by the insertion of extra methylene residues (n = 3 through 9) between the nitrogen and phosphorus atoms of the headgroup. Vesicles were formed from these lipids and studied by 22Na permeability measurements, differential scanning calorimetry, fluorescence polarization, 31P-NMR, and freeze-fracture electron microscopy. Vesicles composed of lipids with n = 2 or 3 exhibit a sharp transition at 46°C or 49°C, respectively, and a high enthalpy with no detectable sub- or pretransitions. Lipids with n > 3 exhibit a main transition between 38 and 43°C with enthalpies < 10 kcal/mol and after prolonged cooling (more than 3 days at 4°C) a broad endotherm at about 20 ± 3°C with enthalpies > 4 kcal/mol. These same dispersions display a permeability peak at 20–25°C and a second increase in 22Na efflux in the temperature range 30–40°C. The results of 31P-NMR measurements suggest that the acyl chains in 2,3-dipalmitoylcyclopentanol-phosphocholine (n = 2) bilayers have restricted rotation below the main phase transition temperature.  相似文献   
102.
Summary The effect of the salinity, alkalinity and Fe application on the dry matter yield and availability of Fe, Mn, P and Na were studied in the greenhouse on pea (Pisum sativum L.) crop. The highest dry matter yield was recorded in normal soil which decreased with the increase in the salinity and alkalinity, minimum being at 40 ESP. Alkalinity was more harmful to pea crop than salinity.Fe at 10 ppm increased the dry matter yield significantly. Highest Fe concentration (408.12 ppm) was recorded in 40 ESP soil followed by 20 ESP (395.2 ppm). Salinity alongwith marginal or higher alkalinity reduced harmful effect of alkalinity. The uptake of Fe was the highest in normal soil due to the high dry matter yield. All the three sources increased the concentration of Fe and its uptake than the control in all the soils but did not show much distinction among themselves.The concentration of Mn decreased more with the increase in alkalinity than salinity but salinity with alkalinity improved Mn concentration. Similarly uptake of Mn also decreased sharply with the increase in salinity and alkalinity. The application of Fe sources decreased Mn concentration but increased the uptake. The highest decrease was caused with FeSO4 and lowest with Fe rayplex.Like Mn the concentration and uptake of P decreased with the increased levels of salinity and alkalinity. The addition of Fe decreased the concentration of P, highest depression being with Fe KE-MIN.Increase in ESP increased the concentration and the uptake of Na greatly. Addition of Fe through all the sources increased Na concentration and uptake significantly but sources did not differ much in their effect on Na.  相似文献   
103.
Neurochemical Research - Growing experimental evidences have suggested the reciprocal correlation between sleep deprivation and pain. Inflammation and oxidative stress are among the key pathways...  相似文献   
104.
Reaction progress curves for the hydrolysis of dimyristoylphosphatidylcholine by pig pancreatic phospholipase A2 exhibits a latency phase. Addition of 1-palmitoyllysophosphatidylcholine to the preformed vesicles reduces the latency phase and enhances the binding of phospholipase A2 to the vesicles. In contrast, the binary codispersions prepared from diacylphospholipids premixed with lysophosphatidylcholine do not exhibit such enhanced susceptibility to the phospholipase. This effect appears to be due to organizational defects created by asymmetrical incorporation of lysophospholipid molecules into the outer monolayer of the vesicles, and the action of phospholipase is not observed when the additive is equilibrated in both the monolayers of the vesicles.  相似文献   
105.
We report the synthesis, spectroscopic properties and intracellular imaging of recombinant antibody single chain fragment (scFv) conjugates with photosensitizers used for photodynamic therapy of cancer (PDT). Two widely-studied photosensitizers have been selected: preclinical pyropheophorbide-a (PPa) and verteporfin (VP), which has been clinically approved for the treatment of acute macular degeneration (Visudyne). Pyropheophorbide-a and verteporfin have been conjugated to an anti-HER2 scFv containing on average ten photosensitizer molecules per scFv with a small contribution (相似文献   
106.
107.
The localization of estrogen receptor (ER)β in mitochondria suggests ERβ-dependent regulation of genes, which is poorly understood. Here, we analyzed the ERβ interacting mitochondrial as well as nuclear proteins in mouse brain using pull-down assay and matrix-assisted laser desorption ionization mass spectroscopy (MALDI-MS). In the case of mitochondria, ERβ interacted with six proteins of 35-152 kDa, its transactivation domain (TAD) interacted with four proteins of 37-172 kDa, and ligand binding domain (LBD) interacted with six proteins of 37-161 kDa. On the other hand, in nuclei, ERβ interacted with seven proteins of 30-203 kDa, TAD with ten proteins of 31-160 kDa, and LBD with fourteen proteins of 42-179 kDa. For further identification, these proteins were cleaved by trypsin into peptides and analyzed by MALDI-MS using mascot search engine, immunoprecipitation, immunoblotting, and far-Western blotting. To find the consensus binding motifs in interacting proteins, their unique tryptic peptides were analyzed by the motif scan software. All the interacting proteins were found to contain casein kinase (CK) 2, phosphokinase (PK)C phosphorylation, and N-myristoylation sites. These were further confirmed by peptide pull-down assays using specific mutations in the interacting sites. Thus, the present findings provide evidence for the interaction of ERβ with specific mitochondrial and nuclear proteins through consensus CK2, PKC phosphorylation, and N-myristoylation sites, and may represent an essential step toward designing selective ER modulators for regulating estrogen-mediated signaling.  相似文献   
108.
Pigeonpea (Cajanus cajan) is an important grain legume of the Indian subcontinent, South-East Asia and East Africa. More than eighty five percent of the world pigeonpea is produced and consumed in India where it is a key crop for food and nutritional security of the people. Here we present the first draft of the genome sequence of a popular pigeonpea variety ??Asha??. The genome was assembled using long sequence reads of 454 GS-FLX sequencing chemistry with mean read lengths of >550?bp and >10-fold genome coverage, resulting in 510,809,477?bp of high quality sequence. Total 47,004 protein coding genes and 12,511 transposable elements related genes were predicted. We identified 1,213 disease resistance/defense response genes and 152 abiotic stress tolerance genes in the pigeonpea genome that make it a hardy crop. In comparison to soybean, pigeonpea has relatively fewer number of genes for lipid biosynthesis and larger number of genes for cellulose synthesis. The sequence contigs were arranged in to 59,681 scaffolds, which were anchored to eleven chromosomes of pigeonpea with 347 genic-SNP markers of an intra-species reference genetic map. Eleven pigeonpea chromosomes showed low but significant synteny with the twenty chromosomes of soybean. The genome sequence was used to identify large number of hypervariable ??Arhar?? simple sequence repeat (HASSR) markers, 437 of which were experimentally validated for PCR amplification and high rate of polymorphism among pigeonpea varieties. These markers will be useful for fingerprinting and diversity analysis of pigeonpea germplasm and molecular breeding applications. This is the first plant genome sequence completed entirely through a network of Indian institutions led by the Indian Council of Agricultural Research and provides a valuable resource for the pigeonpea variety improvement.  相似文献   
109.
Glutathione synthetase (gshB) has previously been reported to confer tolerance to acidic soil condition in Rhizobium species. Cloning the gene coding for this enzyme necessitates the designing of proper primer sets which in turn depends on the identification of high quality sequence similarity in multiple global alignments. In this experiment, a group of homologous gene sequences related to gshB gene (accession no: gi-86355669:327589-328536) of Rhizobium etli CFN 42, were extracted from NCBI nucleotide sequence databases using BLASTN and were analyzed for designing degenerate primers. However, the T-coffee multiple global alignment results did not show any block of conserved region for the above sequence set to design the primers. Therefore, we attempted to identify the location of common motif region based on multiple local alignments employing the MEME algorithm supported with MAST and Primer3. The results revealed some common motif regions that enabled us to design the primer sets for related gshB gene sequences. The result will be validated in wet lab.  相似文献   
110.
The present study was aimed to assess the combined effects of cyclooxygenase and 5-lipoxygenase (COX/5-LOX) inhibitors in different animal models of nociception. Naproxen, nimesulide and rofecoxib are well-established antinociceptive agents acting via COX inhibition. AKBA (acetyl-keto-beta-boswellic acid) is a 5-LOX inhibitor. AKBA (50-200 mg/kg) produced a dose dependent and significant antinociceptive effect in different animal models of nociception. Based on the earlier reports from our laboratory, sub effective doses of all the three COX Inhibitors were selected and they were administered (naproxen, 5 mg/kg; nimesulide, 1 mg/kg; and rofecoxib, 1 mg/kg) with AKBA (100 mg/kg). This produced a more significant antinociceptive effect as compared to per se effect observed in all the three models of nociception. However, the effect of combination of nimesulide with AKBA was more pronounced as compared to naproxen and rofecoxib and their combination with AKBA. The present finding provided an evidence for the potentiation of antinociceptive effect of NSAIDs with AKBA. Such a combination may help to reduce the therapeutic doses of conventional NSAIDs and also reduce side effects (gastric, cardiac and renal) that are popularly associated with the NSAIDs.  相似文献   
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